Information which specifies a person present in a certain place (region) is useful for providing a service customized for marketing surveys or user preference or needs. In recent years, with development of information and telecommunication infrastructure and sensor networks, spread of portable terminals, or the like, a technology in which personal identification is performed in various ways has been proposed.
For example, a technology in which personal recognition is performed using biological information, such as facial recognition, has been provided. In the personal recognition using such biological information, for example, biological information such as a facial pattern has to be registered, for each user. Therefore, it is difficult to specify a person among targets of unspecified users present in a public place, or the like.
Therefore, today the portable terminals are widely spread and a technology, in which a person present in a predetermined region is specified through linkage between information acquired by a surroundings-side sensor network, which can detect a state of surroundings, and information acquired from a portable terminal which is carried by the person, has been proposed. According to this technology, without performing prior information registration such as registration of biological information such as a facial pattern, it is possible to provide a specific service to the portable terminal which is carried by a specified person.
For example, a technology, in which the localization of an accelerometer within a camera view is performed based on the correlation between acceleration data obtained through tracking feature points extracted from a camera image and acceleration data obtained from a built-in accelerometer in the portable terminal, has been proposed.
In addition, a technology, in which location information of all the users present in the surroundings, which is obtained by a tracking system using a camera, is regularly transmitted to a portable terminal, has been proposed. In this technology, the portable terminal generates a track from continuously received location information, stores the tracks as a symbolized list, continuously estimates a user's walking state from data obtained by a built-in motion sensor in the portable terminal, and stores the state in time series. Also, the portable terminal collates the track and the walking state and specifies a track of the portable terminal user from all of the tracks.
In addition, a technology, in which a motion change of a moving object on a camera image is matched with a motion change obtained from an accelerometer installed on the moving object, and thereby the moving object is identified on the camera image, has been proposed.
In addition, a technique, in which three-dimensional positional data of a subject is obtained by combining a video camera image and data from an accelerometer, has been proposed. In the technique, without performing the integral or differential of data combination from a plurality of sensors, acceleration obtained by a sensor and a speed obtained from differences between frames of camera images are collated and IDs of subjects are collated.